Glow sticks are a type of chemiluminescence, which is a chemical reaction that produces light. The light is produced when two chemicals, a dye and an oxidizer, are mixed together. The dye absorbs energy from the oxidizer and then releases it as light.
Glow sticks are often used for safety purposes, such as marking trails in the dark or signaling for help. They are also popular for use at parties and concerts. Glow sticks are relatively inexpensive and easy to use, making them a popular choice for a variety of applications.